Well cleaning apparatus

ABSTRACT

Systems, apparatus and methods are described that can be used for cleaning wells using unfiltered fluids and fluids that contain solid matter. Spray nozzles cooperate with deflectors to direct and outflow of the apparatus to surfaces to be cleaned. The apparatus comprises a mixer having an inner chamber, an inlet and a plurality of outlets. Deflectors are attached to associated outlets. The inner chamber has an impact surface located opposite the inlet, the impact surface redirecting the flow of fluid proportionately to the outlets and minimizes eddies in the flow of fluid. The deflectors generate a force from the fluid flow that includes rotational and/or translational components sufficient to cause rotation about a first axis and/or translation along a second axis.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present Application claims priority from U.S. Provisional PatentApplication No. 61/167,851 filed Apr. 8, 2009, entitled “Improved WellCleaning Apparatus,” which application is expressly incorporated byreference herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to well cleaning equipment andmore particularly to in-well cleaning apparatus.

2. Description of Related Art

Sewage systems are in wide spread use for the removal of liquid wastefrom houses, factories and agricultural sites. The sewage flows throughpipes into intermediate wells and finally into treatment plants or wastedumps. Electric pumps are usually used to maintain the flow and keep thewells below maximum capacity. These pumps are configured to operate whenthe level in the wells reaches a preset limit indicating that the flowneeds pumping.

When the well level falls to a minimum level the pump is switched offand this level may be maintained for some time leaving a biofilm residueon the walls of the well between the maximum and minimum levels. Thisresidue tends to harden and build up thus reducing the capacity of thewell, and increasing the frequency of the pump operation.

Wastewater collection and treatment systems are a source of bad odors,the most prevalent coming from Hydrogen Sulphide, a toxic and corrosivegas with a characteristic rotten-egg smell. This is a bacteriallymediated process that occurs in the submerged portion of sanitarysewerage systems. It begins with the establishment of a slime layerbelow the water level, composed of bacteria and other inert solids heldtogether by a biologically secreted protein “glue” or biofilm calledzooglea. When this biofilm becomes thick enough to prevent the diffusionof dissolved oxygen, an anoxic zone develops under the surface.

Hydrogen Sulphide is also a precursor to the formation of SulphuricAcid, which causes the destruction of metal and concrete substrates andappurtenances within wastewater facilities and collection stations. Theeffect of biogenic sulfide corrosion and the formation of a 7% SulphuricAcid solution on concrete surfaces exposed to the sewer environment aredevastating. Entire pump stations and manholes and large sections ofcollection interceptors have collapsed due to the loss of structuralintegrity in the concrete. Accordingly the residue must be cleaned offthe well walls and removed from the surface of the sewer waterperiodically to maintain the system in good working order as well asprotecting concrete structures against the biogenic sulfide corrosion inwastewater collection and treatment systems so as to met the structure'santicipated design life as well as protecting the surrounding groundlevel infrastructure and environment.

Obstructions of the nozzles in prior art systems present seriousdifficulties in the operation of well cleaning apparatus. Well cleaningequipment must be frequently removed for cleaning as solid materialsbuild up on the inner surfaces of the nozzles. Nozzles must be cleanedand, in some instances cleaning devices must be disassembled forcleaning on a regular basis.

BRIEF SUMMARY OF THE INVENTION

Certain embodiments of the present invention comprise systems andmethods for which overcome or at least significantly reduce problemsrelating to the cleaning of wells by prior art systems. In particularthe present invention employs spray nozzles and a submerged pumpingsystem which allows the apparatus to use the sewage in the well to cleanthe walls causing aeration of the introduced effluent, hydrating thegrease, oils, fats that contribute to biofilm so that it can be easilytransported, via the sewer system to treatment plant for treatment.Systems and apparatus according to certain aspects of the invention canuse a liquid stream containing solid materials which prior art apparatushas not achieved. Apparatus may be provided at well openings, removingthe need for confined space entry. In certain embodiments, apparatus canbe easily repositioned from the well entry point to allow access to thewell to facilitate maintenance.

Certain embodiments of the invention provide apparatus that comprises amixer having an inner chamber, an inlet and a plurality of outlets andone or more deflectors attached to associated outlets. In some of theseembodiments, each deflector directs a fluid received from its associatedoutlet to a surface within a well. In some of these embodiments, themixer receives a pressurized, unfiltered flow of fluid at the inlet andsplits the supply of fluid between the outlets.

In certain embodiments, the inner chamber includes an impact surfacelocated opposite the inlet, the impact surface redirecting the flow offluid proportionately to the outlets. In some of these embodiments, theimpact surface is curved and has an apex opposite the inlet. In some ofthese embodiments, the radius of curvature is selected to minimizeeddies in the flow of fluid. In some of these embodiments, the radius ofcurvature is selected to obtain uniformity of fluid pressure throughoutthe inner chamber. In some of these embodiments, the radius of curvatureis selected to obtain a desired distribution of fluid pressurethroughout the inner chamber.

In some of these embodiments, the deflectors generate a force from thefluid flow that includes rotational and/or translational componentssufficient to cause rotation about a first axis and/or translation alonga second axis. The first and second axes can be the same axis or relatedaxes. In some of these embodiments, the magnitudes of the forces arecontrolled by an angle at which the deflector is attached to itsassociated outlet. In some of these embodiments, the magnitude of theforce is controlled to obtain a speed of rotation of the apparatus. Insome of these embodiments, the magnitude of the force is controlledusing a spring. In some of these embodiments, the magnitude of the forceis controlled using aerodynamic members attached to one of thedeflectors. In some of these embodiments, the magnitude of the force iscontrolled using aerodynamic members attached to the mixer. In some ofthese embodiments, the magnitude of the force is controlled usinghydrodynamic members attached to one of the deflectors. In some of theseembodiments, the magnitude of the force is controlled using hydrodynamicmembers attached to one of the deflectors.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an elevation depicting an example of the presently claimedapparatus deployed within a well.

FIG. 2 shows a cross-sectional view of a mixer according to certainaspects of the invention.

FIG. 3 shows variously angled views of a deflector according to certainaspects of the invention.

FIG. 4 is a detailed view of a mixer.

FIG. 5 is a detailed view of a mixer.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the present invention will now be described in detailwith reference to the drawings, which are provided as illustrativeexamples so as to enable those skilled in the art to practice theinvention. Notably, the figures and examples below are not meant tolimit the scope of the present invention to a single embodiment, butother embodiments are possible by way of interchange of some or all ofthe described or illustrated elements. Wherever convenient, the samereference numbers will be used throughout the drawings to refer to sameor like parts. Where certain elements of these embodiments can bepartially or fully implemented using known components, only thoseportions of such known components that are necessary for anunderstanding of the present invention will be described, and detaileddescriptions of other portions of such known components will be omittedso as not to obscure the invention. In the present specification, anembodiment showing a singular component should not be consideredlimiting; rather, the invention is intended to encompass otherembodiments including a plurality of the same component, and vice-versa,unless explicitly stated otherwise herein. Moreover, applicants do notintend for any term in the specification or claims to be ascribed anuncommon or special meaning unless explicitly set forth as such.Further, the present invention encompasses present and future knownequivalents to the components referred to herein by way of illustration.

Embodiments of the present invention can be deployed in well cleaningapparatus in order to improve the efficiency and effectiveness of suchequipment. Wells may contain a body of fluid comprising waste materialsor other solids, including, for example sewage, storm run-off, fluidscollected from cleaning equipment, agricultural wastes and so on. Forthe purposes of this description, an example of well cleaning apparatuswill be used that bears certain similarities to apparatus described inthe application filed under the patent cooperation treaty and numberedPCT/AU2007/001083 (and incorporated by reference herein in itsentirety). Certain embodiments of the present invention can be used toretrofit conventional well cleaning apparatus but it will be appreciatedthat certain components of well cleaning equipment may be adapted and/orreconfigured to maximize the advantages accrued from the presentinvention. In some embodiments, for example, pump operatingcharacteristics may be loosened because spray assemblies according tocertain aspects of the invention can disperse accretions of solidsdeposited during variations in pump output. PCT application No.PCT/AU2007/001083 is incorporated by reference herein in its entirety.

As depicted in FIG. 1, a well cleaning apparatus according to certainaspects of the invention can be mounted on, or suspended from a frame orbracket 11 typically attached by fasteners 12 at the top of well, tank,drum, vault or other container 10. For the purpose of description, theterms well, tank, drum, vault, sump or other container will be usedhenceforth interchangeably; “well 10” will be commonly used to describeany such container. Fluid is transmitted through a pipe or hose 17 to aconduit 14 and from there to spray assembly 15 which directs jets offluid using deflectors 16 of spray assembly 15. In certain embodiments,spray assembly 15 is rotatably mounted to conduit 14 such that sprayassembly 15 may rotate around axis of rotation 13 in order to obtainrotating water jets. Rotation is typically driven by force of waterpressure. In operation, jets may provide a spray to the walls of thewell 10, the surface of liquids 100 in the well 10 or tank and otherequipment located within the well 10. The hose or pipe 17 is typicallycoupled to the conduit at coupling 18 and the fluid provided forcleaning can be obtained from an external source of water or derivedfrom effluent pumped from the well by a submersible or other pump 19. Itwill be appreciated that, in conventional systems, pump 19, conduit 14,coupling 18 and jets may be subject to clogging, even where the systemand its components are designed to pass anticipated solids such as, forexample, solids up to 50 mm in diameter and 90 mm long found in a sewagestream.

Certain embodiments of the present invention provide a spray assembly 15for use in an automatic well washer that can reduce and/or eliminate theoccurrence of blockage from accumulation of solid matter in a fluidstream used to wash the well, vault or tank. Referring to FIGS. 2 and 3,a spray assembly according to certain aspects of the invention typicallycomprises a mixer 20 and one or more deflectors 30 that cooperate todirect a flow of fluid to spray to the walls of the well 10, the surfaceof liquid 19 in the well 10 and other equipment located within the well10. Mixer 20 is configured to optimize, control and generate flows andcurrents that prevent buildup of solid materials in an interior chamber22 of mixer 20 and on the deflectors 30. Deflectors 30 are typicallyused to direct the flow of fluid to a target area for cleaning and maybe angled or tilted in a manner that causes the spray head to rotate.

The examples depicted are dimensioned according to the requirements of asewage treatment application. The depicted devices can be scaledaccording to need, although it will be appreciated that the dimensionsof certain elements may remain constant or be scaled to a lesser degree.In the example shown in FIG. 2, inlet 24 has a substantially cylindricalportion that has a diameter that is similar to, or the same as thediameter of corresponding substantially cylindrical portions of outlets26 and 28. In the example, an inner diameter of the cylindrical portionsis dimensioned as approximately 2.4 inches. In at least someembodiments, the inner surface of one or more of inlet 24 and outlets 26and/or 28 may be threaded for attaching pipes, vanes, deflectors and thelike. In the example, the axes of outlets 26 and 28 are each angled atapproximately 43.75°. Impact surface 220 of chamber has curved surfacethat is typically elliptical, parabolic or circular in profile. As shownin the example of FIG. 2, a typical device for use in sewage treatmenthas a generally circular impact surface 220 having a radius of curvatureof approximately 10.5 inches.

In conventional systems, eddy currents may create areas of low pressurewithin a spray head and variations in pressure may be observed during apumping cycle, or when a flow fluid or liquid through the system and/orwhen a pump ceases operation. In response to such variations,conventional equipment may become progressively clogged as solids settleat junctions or distributors (e.g. in a tee piece), in small diameterpipe lines, fittings, bends, elbows, valves and areas of low pressure.Clogging can lead to partial or complete obstruction of the system.However, a mixing chamber constructed according to certain aspects ofthe invention avoids the potential for obstruction. For example, thecurvature of impact surface 220 may be selected based on anticipatedviscosity of treated fluids and characteristics of the solid materialscontained therein.

Certain embodiments provide a spray assembly 15 that includes mixer 20having specifically engineered curves calculated to provide clog freeoperation of washer head using un-filtered stream of sewer water, stormwater or the like. The example of FIG. 2 shows one embodiment wheredimensions are typical for use in many sewage applications. Radii ofcurvature, cross-sectional diameters and other dimensions are selectedbased on parameters attributable to the application, including range ofviscosity of the fluid, maximum and minimum size of solids, pressuredeveloped by pump 19 and operating temperatures. Fluid flowing intochamber 22 from inlet 24 is directed to outlets 26 and 28. An impactsurface 220 defined generally opposite the inlet is constructed tominimize undesired reflections and resultant waves, eddies and vorticesin the fluid. Thus, the fluid flows through chamber 22 relativelysmoothly. In some embodiments, the fluid can be caused to swirl, rotateor be otherwise agitated as desired.

In particular, the structure, location and dimensions of certain curvedsections are calculated to enable free flow of un-filtered liquids.Fluid entering a first orifice 24, which serves as an inlet, passes tointerior chamber 22 where the flow splits and exits the interior chamber22 through other orifices 26 and 28 that serve as outlets to vent theliquid. The shape and dimensions of interior chamber 22 are selected tocause deposits of solids and bio-solids to be rolled and circulated intothe liquid passing through the interior chamber 22. Solids andbio-solids are then pushed by the liquid flow liquid out of outlets 26and 28.

In certain embodiments, mixer 20 can cause liquid to flow around solidsand otherwise apply pressure to solids which have previously settledwithin interior chamber 22, including settlements occurring due to endof a pump cycle or during periods of low fluid flow. The structure ofinterior chamber 22 can create an agitation that causes accumulatedsolids and/or bio-solids to be lifted and circulated and eventuallycarried through outlets 26 and 28.

FIG. 3 depicts various views of a deflector 30 that can be used inconjunction with spray assembly 15. One or more deflectors 30 can beattached to mixer 20. In certain embodiments, deflector 30 is designedto respond to hydrodynamic forces created by the liquid as it isexpelled through outlets 46 and 48. As the fluid passes over surfaces ofthe deflector 30, it may exert direct pressure on the surfaces ofdeflector 30 and/or generate aerodynamic or hydrodynamic pressuredifferences that cause the desired rotation. Thus, the volume andpressure of the liquid forced out of the mixer 20 can be used to causeand control rotation of the spray assembly. Rotation typically occurswhen deflector 30 is suitably angled with respect to the outflow fromoutlets 26 and 28 and with respect to an axis of rotation 13 of thespray assembly. Thus, deflector 30 may have a “park” angle at whichdeflector 30 causes no rotational motion.

In certain embodiments, speed of rotation can be controlled byconfiguration and position of deflectors 30. A desired speed of rotationcan be selected in this manner. Typically the angle of deflector 30relative to an axis of rotation 13 of the spray assembly is selected tocontrol speed of rotation. Speed of rotation may be automaticallycontrolled to limit rotation to the desired speed of rotation by varyingthe angle and position of deflectors based on current speed of rotation.In particular, angle and/or position of deflectors 30 may beautomatically adjusted in response to changes in pressure and volume ofliquid passing through the outlets 26 and 28 of mixer 20. Consequently,the disclosed system may accommodate a broad range of pumps 19 and modesof operation of those pumps 19. For example, the system may accommodatea pump 19 driven at different rates selected to obtain differentthroughputs.

In certain embodiments, a pre-tensioned spring system can be used tocontrol angle and or position of deflectors 30 based on actual speed ofrotation. Such control can reduce liquid dispersal to a “ribbon action”and can prevent aerosol action and/or misting that can cause release ofH₂S and other undesired gas components. In some embodiments, speed ofrotation may be automatically controlled using aerodynamic orhydrodynamic elements attached to the deflector and/or mixer 20, wherebythe additional elements generate a force resistant to rotationproportional to the speed of rotation of spray assembly 15.

In certain embodiments, spray assembly 15 may be free to translate alongthe axis of rotation under the force of the outflow from outlets 26 and28. Additional mechanisms may adjust the angle and direction of thedeflector 30 after translation a predetermined distance, causing areversal in direction and resulting in an oscillation of the sprayassembly 15 that increases the area treated by the system. In certainembodiments the form, size and angle of the deflectors 30 can be used tocontrol surface area of spray coverage.

The spray assembly 15 may be operated in applications where full-sizesolids are required to pass through freely without obstruction andclogging at various volumes and pressures. Full-size solids includesolids that can pass through an inlet orifice having a predetermineddiameter.

In certain embodiments, liquids containing solids and/or bio-solidspassing through mixer 20 are typically agitated, oxygenated andhomogenized. Moreover, a surface of a liquid contained by the well maybe agitated, oxygenated and homogenized by the action of spray assembly15. In addition to agitation, oxygenation and homogenization substancessuch as fat, oil, grease and bio-film present on the surface of theliquid in the well may be solubilized.

In certain embodiments, mixer 20 can be sized to accommodate otheroutflows without fixing a new mixing chamber by simply attaching flowreducers to outlet orifices.

FIGS. 4 and 5 are engineering drawings showing detailed designinformation associated with one example of a spray assembly 15 accordingto certain aspects of the invention.

Additional Descriptions of Certain Aspects of the Invention

The foregoing descriptions of the invention are intended to beillustrative and not limiting. For example, those skilled in the artwill appreciate that the invention can be practiced with variouscombinations of the functionalities and capabilities described above,and can include fewer or additional components than described above.Certain additional aspects and features of the invention are further setforth below, and can be obtained using the functionalities andcomponents described in more detail above, as will be appreciated bythose skilled in the art after being taught by the present disclosure.

Certain embodiments of the invention provide a spray apparatus that maybe used in cleaning wells. The apparatus typically comprises a mixerhaving an inner chamber, an inlet and a plurality of outlets and one ormore deflectors attached to associated outlets. In some of theseembodiments, each deflector directs a fluid received from its associatedoutlet to a surface within a well. In some of these embodiments, themixer receives a pressurized, unfiltered flow of fluid at the inlet andsplits the supply of fluid between the outlets.

In some of these embodiments, the inner chamber includes an impactsurface located opposite the inlet, the impact surface redirecting theflow of fluid proportionately to the outlets. In some of theseembodiments, the impact surface is curved and has an apex opposite theinlet. In some of these embodiments, the radius of curvature is selectedto minimize eddies in the flow of fluid. In some of these embodiments,the radius of curvature is selected to obtain uniformity of fluidpressure throughout the inner chamber. In some of these embodiments, theradius of curvature is selected to obtain a desired distribution offluid pressure throughout the inner chamber.

In some of these embodiments, the fluid includes solids. In some ofthese embodiments, the solids comprise bio-solids. In some of theseembodiments, the desired distribution of fluid pressure is sufficient todislodge solids accumulated solids in the inner chamber.

In some of these embodiments, wherein the deflectors generate a forcefrom the fluid flow. In some of these embodiments, the force includes arotational component sufficient to cause rotation of the apparatus. Insome of these embodiments, the magnitude of the force is controlled byan angle at which the deflector is attached to its associated outlet. Insome of these embodiments, the magnitude of the force is controlled toobtain a speed of rotation of the apparatus. In some of theseembodiments, the magnitude of the force is controlled using a spring. Insome of these embodiments, the magnitude of the force is controlledusing aerodynamic members attached to one of the deflectors. In some ofthese embodiments, the magnitude of the force is controlled usingaerodynamic members attached to the mixer. In some of these embodiments,the magnitude of the force is controlled using hydrodynamic membersattached to one of the deflectors. In some of these embodiments, themagnitude of the force is controlled using hydrodynamic members attachedto one of the deflectors.

In some of these embodiments, the force includes a translationalcomponent sufficient to translate the apparatus in a direction generallyperpendicular fluid exiting the outlets. In some of these embodiments,the apparatus oscillates along the direction generally perpendicularfluid exiting the outlets.

Although the present invention has been described with reference tospecific exemplary embodiments, it will be evident to one of ordinaryskill in the art that various modifications and changes may be made tothese embodiments without departing from the broader spirit and scope ofthe invention. Accordingly, the specification and drawings are to beregarded in an illustrative rather than a restrictive sense.

1. An apparatus, comprising: a mixer having an inner chamber, an inletand a plurality of outlets; one or more deflectors, each deflectorattached to an associated outlet, wherein each deflector directs a fluidreceived from its associated outlet to a surface within a well andwherein the mixer receives a pressurized, unfiltered flow of fluid atthe inlet and splits the supply of fluid between the outlets.
 2. Theapparatus of claim 1, wherein the inner chamber includes an impactsurface located opposite the inlet, the impact surface redirecting theflow of fluid proportionately to the outlets.
 3. The apparatus of claim2, wherein the impact surface is curved and has an apex opposite theinlet.
 4. The apparatus of claim 3, wherein the radius of curvature isselected to minimize eddies in the flow of fluid.
 5. The apparatus ofclaim 3, wherein the radius of curvature is selected to obtainuniformity of fluid pressure throughout the inner chamber.
 6. Theapparatus of claim 3, wherein the radius of curvature is selected toobtain a desired distribution of fluid pressure throughout the innerchamber.
 7. The apparatus of claim 6, wherein the fluid includes solids.8. The apparatus of claim 7, wherein the solids comprise bio-solids. 9.The apparatus of claim 7, wherein the desired distribution of fluidpressure is sufficient to dislodge solids accumulated solids in theinner chamber.
 10. The apparatus of claim 1, wherein the deflectorsgenerate a force from the fluid flow.
 11. The apparatus of claim 10,wherein the force includes a rotational component sufficient to causerotation of the apparatus.
 12. The apparatus of claim 11, wherein themagnitude of the force is controlled by an angle at which the deflectoris attached to its associated outlet.
 13. The apparatus of claim 11,wherein the magnitude of the force is controlled to obtain a speed ofrotation of the apparatus.
 14. The apparatus of claim 11, wherein themagnitude of the force is controlled using a spring.
 15. The apparatusof claim 11, wherein the magnitude of the force is controlled usingaerodynamic members attached to one of the deflectors.
 16. The apparatusof claim 11, wherein the magnitude of the force is controlled usingaerodynamic members attached to the mixer.
 17. The apparatus of claim11, wherein the magnitude of the force is controlled using hydrodynamicmembers attached to one of the deflectors.
 18. The apparatus of claim11, wherein the magnitude of the force is controlled using hydrodynamicmembers attached to one of the deflectors.
 19. The apparatus of claim10, wherein the force includes a translational component sufficient totranslate the apparatus in a direction generally perpendicular fluidexiting the outlets.
 20. The apparatus of claim 19, wherein theapparatus oscillates along the direction generally perpendicular fluidexiting the outlets.